The authors develop an original measure of learning in higher education, based on grades in subsequent courses. Using this measure of learning, they show that student evaluations are positively related to current grades but unrelated to learning once current grades are controlled. They offer evidence that the weak relationship between learning and student evaluations arises, in part, because students are unaware of how much they have learned in a course. They conclude with a discussion of easily implemented, optimal methods for evaluating teaching. (Contains 8 tables and 17 notes.)